Known in the art is a writing instrument which is provided with a separate erasing member at a top part of a cap whereby marks which are made by that writing instrument on a paper surface etc. can be erased by the erasing member (for example, PLT 1).
Further, PLT 2 describes an attachment structure for attaching a soft member corresponding to an erasing member to the top end part of a body or cap or other tubular member of a writing instrument. According to the attachment structure which is described in PLT 2, a projecting part is provided at the top end part of a tubular member, an attachment hole is provided at the bottom end part of the erasing member, and the projecting part is inserted into the attachment hole for engagement to thereby attach it.